1. Field of Invention
This invention relates generally to the field of rain gutters and downspouts, and particularly to devices that divert the flow of water therefrom.
2. Prior Art
One of the simplest ways to clean gutters and downspouts is by spraying with water, such as that from a garden hose or pressure washer. When downspouts are connected to underground drainage lines, however, water cleansing may cause debris related obstructions in the underground lines. This is especially true when there are frequent bends, long runs, or minimal slopes in the underground pipes. For these reasons, the industry has not recommended liquid rinsing as a preferred method for cleaning downspouts that connect to underground lines.
Building owners and maintainers could benefit greatly from a device that would allow them to rinse gutters and downspouts without the risk of clogging underground lines.
Prior art from the late nineteenth century shows a related field of downspout diversion devices known as cistern cutoffs. In U.S. Pat. No. 60,005 (1866), Hicks and Welcker disclose a cistern cutoff consisting of;                “ . . . a square box . . . provided with an adjustable spout . . . which turns around a hinge . . . by whose means the water running from a roof, etc., of a building, towards a cistern or other receptacle of rainwater, can be turned off, or may be directed to flow into the cistern.”        
Hicks' design may be described as an “out-swing geometry” in that the disclosed “adjustable spout” rotates outwardly from a closed position, flush with the “square box,” or main body, to an operable position, angularly extended across the width of and outward from the main body.
In such “out-swing geometry” devices, as the spout swings outward from above a hinge, a deflection surface, below the hinge, swings inward to redirect the flow of water. As the deflection surface rotates inward, it is required to rotate past 90° (horizontal) to some greater angle sufficient to re-direct water out of the main body. The length of the deflection surface is thus limited by the fact that in the horizontal position its length must allow it to clear the back wall of the main body. As rotation continues beyond horizontal, the end of the deflection surface is caused to pull away from the back wall of the main body. This pulling-away from the back wall results in a gap (herein after referred to as “plate gap”) between the deflection surface and the back wall of the main body, which allows some of the water to escape past the deflection surface.
Hicks addressed the plate gap problem by means of,                “ . . . an extra leader [downspout section] . . . provided inside of the box . . . so excluding the possibility of any water running into the cistern as long as the spout . . . is kept open.”Hicks provided few details, however, as to the means or position of attachment for the “extra leader” with respect to the main body.        
Several other examples of the prior art demonstrated various ways to overcome plate gap in in-swing type cistern cutoff devices.
Perkins, in U.S. Pat. No. 96,478 (1869), discloses a device where the pivot point of the plate is itself rotatable about a linkage attached to the main body. This rotating pivot point allows the deflection surface to translate inward into the main body as the surface is rotated outward.
Lee, in U.S. Pat. No. 125,742 (1872), discloses a device using an inner chamber or “sliding section” to eliminate the plate gap problem.
Wuerz, in U.S. Pat. No. 142,832 (1873), discloses a device with a curved, slotted pivot point rather than a fixed pivot point. This curved, slotted pivot allowed the deflection surface to translate as well as rotate to help reduce plate gap.
West, in U.S. Pat. No. 246,930 (1881), discloses an “inclined ledge” within the main body, such that the rear wall of the main body projects inwardly to close the plate gap.
Fisher, in U.S. Pat. No. 289,821 (1883), discloses a fixed-pivot-point device provided with an inner chamber to “ . . . [deflect] a column or stream of water . . . upon the [diverter surface].”
Weightman, in U.S. Pat. No. 458,768 (1891), discloses a sliding-pivot-point device with interior “guards” to direct water away from the rear wall of the main body.
Then, in 1898, Epple, in U.S. Pat. No. 608,765, would be the first to disclose an “in-swing geometry” cistern cutoff device that eliminated the plate gap problem. Epple's device placed the deflection surface above the hinge and allowed it to rotate inward at an angle less than 90°, where it came to rest against the back wall of the main body.
Epple exploited the advantages of the in-swing geometry by disclosing a cistern cutoff that was free of movable pivot points, inner chambers, and rear-wall flanges or deflectors. Besides this change in geometry, another distinguishing feature of Epple's design was an “out-of-plane” front wall on a portion of the main body. A discussion of out-of-plane walls will be addressed at the end of this section, relating to the topic of leak-resistance.
Harms, in U.S. Pat. No. 3,990,474 (1976), discloses a second example of an in-swing geometry water diversion device. Rather than fixing a pivot point between the main body and the diverter plate, however, Harms allows the diverter plate to tilt and translate about the lower edge of the main body aperture.
Johnson, in U.S. Pat. No. 6,024,127 (2000), discloses a downspout clean out adapter similar in operation to Harms' diverter. Unlike Harms' free floating plate, however, Johnson discloses “guides” that hold the diverter plate in either a vertical or an inclined position.
A disadvantage to Johnson's use of “guides” to position the plate is that it requires the operator to perform six motions—raising, removing, rotating longitudinally (tilting), rotating laterally (flipping), reinserting, and locking downward—to operate the device.
A second disadvantage of Johnson's design is that it specifies a spout (the lower half of the deflection plate that extends outward and downward from the aperture). It can be noted that all other prior art, as well, disclosed the use of a spout on the distal end of the diverter plate. In the earlier cistern cutoff devices, the spout performed two functions; it provided a means to channel the water into a rain barrel for collection, and it functioned as a handle by whose means the plate was repositioned. As Johnson made the shift from a rain collection device to a debris cleanout device for downspouts, however, the channeling function of the spout would no longer be required: Where a cistern cutoff device was designed to collect water, a downspout cleanout device could be allowed to discard it. Johnson, however, could not eliminate the spout because his design required its secondary use as a handle.
By relying on spouted diverter plates, the prior art disclosed designs that are inefficient (in terms of material usage, overall dimensions, and appearance) compared to a device that could be made to function without a spout. For example, the vertical profile of non-spouted device could be reduced by as much as 50% from that of a spouted device by eliminating the lower half of the deflection surface (the spout) and the corresponding length of the main body.
A final aspect of the prior art that warrants discussion is that of leak-resistance features. The remainder of this section will focus on this topic.
In the early cistern cutoff devices, no discussion was made regarding features that inhibited water leakage from the closed aperture.
Wuerz (U.S. Pat. No. 142,832) became the first to suggest the desirability of leak resistance by disclosing that the fit of the spout against the main body, when closed, was to be, “ . . . of such correspondence as to ensure a tight joint.”
West (U.S. Pat. No. 246,930) also touched on the desirability of a leak resistant design by specifying that, when closed, “ . . . the bottom of the spout to [is to] bear closely upon the frame [main body].”
Similarly, Harms (U.S. Pat. No. 3,990,474) describes his device, in the closed position, to be such that, “ . . . the diverter plate lays close along the side wall of the downspout.”
Epple (U.S. Pat. No. 608,765) makes a specific claim regarding an “out-of-plane wall” in his cistern cut-off device. Epple describes moving the upper wall (the wall containing the aperture) outward from the plane of flow and bringing the lower wall (the wall below the aperture) inwardly back into the flow plane. Epple's purpose for this was to specify the proper positioning of the deflection surface's pivot point, which, in this case, was the top edge of the lower wall itself.
Intuitively, it can be seen that Epple might have gained a measure of leak resistance by moving the aperture forward, out of the plane of flow. However, by moving the lower wall back into the plane, Epple effectively reduced any leak-resistance benefits he might have achieved from the upper out-of-plane wall: Rather than transferring fluid from a smaller area above to a larger area below, as one does when pouring fluid from a small container into the larger, open end of a funnel, Epple does the reverse. With the lower flow area smaller than the upper area, the opportunity for fluid leaks from the lower area is increased.
Epple's prior art fails to teach the use of out-of-plane walls as a means of enhancing leak resistance. Thus, the collection of prior art is left with only Wuerz's, West's, and Harm's “tight-fit” approach to addressing the problem of leakage from cistern cutoff type fluid diversion devices.